Field of the Invention
The present invention relates to encrypting methods and decrypting methods of short messages and receiving apparatuses for receiving short messages and, more particularly, to an encrypting method and decrypting method of a security short message and a receiving apparatus for receiving a security short message to enhance security and privacy.
Description of the Prior Art
Due to communication-related technological advancements, conventional modes of mobile communication are no longer restricted to static IP connection, and the applications of mobile communication devices are becoming wider. Among various services of mobile communication, short message service serves as an alternative to phone calls and thereby remains indispensable to mobile communication.
Due to technological advancements, contents transmitted by short message service are increasingly diversified, evolving from early short message service whereby text-based messages are transmitted to later multimedia short message service whereby multimedia files, such as pictures, voices and videos, are transmitted.
Short message service systems of conventional mobile devices have drawbacks in terms of the privacy and security of short messages. For example, with a short message service system being an application, contents of a short message can still be intercepted with a built-in program of mobile devices and therefore maliciously copied and saved on the other devices. Furthermore, the contents of a short message used by a conventional short message service system are mostly plaintext and do not undergo encryption or format conversion, and in consequence the short message is likely to be cracked by a third party. Moreover, a conventional short message service system never verifies the purposes of short messages sent and therefore always poses a security risk; for instance, a short message intended to be sent to a first device may be wrongly sent to a second device, thereby allowing the second device to receive and read the short message. Also, after receiving a short message inclusive of an execution instruction, a conventional short message service system always executes the execution instruction right away without examining related information available at the transmitting end, and in consequence the third party is able to control mobile devices through the short message easily. Last but not least, the conventional short message service system never verifies the sending time of a short message, thereby increasing the chance that the same short message will affect mobile devices repeatedly.